While the Indian Head Central trains are no longer in operation, this line is not technically abandoned. While no trains have operated over it for a couple of years, there are plans to resume freight service in the future. An SW8 (#2037) has been purchased by the Government, with plans for it to be refurbished. (Thanks to Josh at the Indian Head Naval Warfare center for this updated information).
The US Navy operated this branch line in Charles County, Maryland, that runs from the CSX (formerly Pennsylvania RR) Popes Creek Secondary from White Plains, past Rasmussens Siding to the Indian Head Naval Ordnance Station on the east bank of the Potomac River. The tracks were intact and the grade crossing signs and signals are still all in place as of spring 2003.
The now defunct Indian Head Central leased the tracks for tourist / passenger service for a couple of years. The IHC posted a few signs at crossings along the right of way, but there is no currently operating passenger or freight trains. The FP10 that they had used is now stored at the power plant near Morgantown.